1. Field of Invention
The present invention relates to a front axle of an agricultural tractor.
2. Background of Prior Art
The present invention relates to a front axle of a tractor of the type described, for example, in Italian Patent Application BO98A000676, to which the following description refers purely by way of example.
In the farm machinery sector, a tractor is known comprising a front axle supporting two front wheels of the tractor, and in turn comprising an elongated box body, and two lateral members, each of which is engaged in rotary manner by one of the wheels, and is hinged to the box body to rotate, with respect to the box body, about a respective hinge axis.
The box body has a central cavity, which houses a differential of a transmission assembly for transmitting power from an input shaft to the wheels, and which is closed by a cover at which the axle is connected to a free end of a supporting bar placed crosswise to the box body and for also supporting at least one upright supporting a frame of the tractor.
The angular position of the lateral members about the respective hinge axes is controlled by a steering assembly comprising at least one steering actuating cylinder acting on one of the lateral members, and a connecting bar extending between the lateral members, and which, when steering, oscillates about an instantaneous axis of rotation movable with a given law of motion, one component of which is parallel to the longitudinal axis of the tractor.
Known front axles of the above type therefore have the major drawback that, when the connecting bar is necessarily located behind the box body in the travelling direction of the tractor, to keep the front part of the tractor clear, e.g. to attach an operating unit, the distance between the supporting upright and the box body is greater than a given value to enable the instantaneous axis of rotation to move parallel to the longitudinal axis of the tractor, so that the tractor has a relatively long wheel base.